Scaffold platform

ABSTRACT

A scaffold platform comprising a pair of joist supporting and secured to a deck plate, with their ends so fabricated that they can be disposed on a scaffold to furnish an elongated horizontal platform for the support of building materials and workmen, and for use as a walkway.

i/nite Mates ntent William E. Gilbreath;

Edward C. Gilhreatli, both of Houston, Tex.

Apr. 6, 1970 Dec. 21 197 1 Bleacher Sales Co.

Houston, Tex.

inventors Appl. No. Filed Patented Assignee SCAFFOLD PLATFORM 4 Claims,7 Drawing Figs.

U.S.Cl 182/222 llnt.Cl E04g5/08 Field of Search 182/222,

[56] llteierences Cited UNITED STATES PATENTS 1,995,514 3/1935 Martin52/483 2,261,831 11/1941 Farr 182/223 3,306,397 2/1967 Brumenshenkel182/223 3,434,567 3/1969 Wilkins 182/222 Primary Examiner-Reinaldo P.Machado Attorney-Roy 1-1. Smith, Jr.

ABSTRACT: A scaffold platform comprising a pair of joist supporting andsecured to a deck plate, with their ends so fabricated that they can bedisposed on a scaffold to furnish an elongated horizontal platform forthe: support of building materials and workmen, and for use as awalkway.

PATENTEB BEEN H7! SHEET 1 [1F 2 WlLLlAM E. GILBREATH EDWARD C GILBREATHI'NVENTURS FIGURE 3 FIGURE 4 ATTORNEY FATENTEU 05:21 1971 3628;628

sum 2 OF 2 FIGURE 7 WILLIAM E. GILBREATH EDWARD C. GILBREATH INVEN'I'OR.

BY@XM27.

FIGURE 6 ATTORNEY SCAFI ULD PLATFORM The present invention lies in thefield of platforms used as walkways and as a support for workingmaterials and the workmen engaged in construction or maintenance, e.g.,bricklayers, carpenters, painters, and the like. The platform of theinvention may be used singly, but finds its most typical and widestrange of uses when it is one section of an elongated platform formed bythe use of a multiplicity of similar platforms, typically disposed on ascaffold or framework so that the upper surfaces of the platforms lie ina common horizontal plane forming an elongated walkway or working space.

One object of the invention is to provide a scaffold platform which islight in weight, easily handled by one workman, and yet is extremelystrong under the forces common to scaffold platforms, having a breakingstress under vertical loading well in excess of the loads that can beexpected in normal service and even in unusually demanding service, bothas to static and dynamic loads.

Another object of the present invention is to provide such a scaffoldplatform adapted for use in multiples, i.e., with their ends sofabricated that they can be disposed on a scaffold platform withabutting ends to furnish an elongated horizontal platform for thesupport of building materials and workmen, and for use as a walkway.

Another object is to supply such a platform which includes one or more,typically a pair of lightweight metal joists which may be inexpensivelyextruded and yet will have all the strength of a much heavier, solidwood beam.

Another object is to provide a scaffold platform using such joist orjoists underlying and so secured to a deck plate that the combinationproduces a unitary structure which is unusually strong under the bendingstresses normal in supporting vertical loads imposed thereon in service.

Another object is to provide such a scaffold platform requiring no tierods, cross bracing, or other members extending transversely between thejoists of the structure, the entire platform consisting only of a deckplate and one or more joist underlying and secured to such deck plate.

Another object is to provide such a scaffold platform in which the deckplate may be made of inexpensive and readily replaceable yet quitestrong material such as plywood.

A further object is to provide a scaffold platform including a pair ofjoists supporting and secured to a deck plate of plywood or similarmaterial, such joists being disposed adjacent opposed edges of the deckplate and at least one of them having a flange which is extended andbent around such edge of the deck plate to cover and protect it.

The above objects are generally attained according to the invention bythe combination of a thin deck plate and one or more joists of specialshape underlying and secured to the deck plate at closely spacedintervals along the length of each joist. When the deck plate consistsof a metal member such as commonly used in ships, the extrudedrnetaljoist may be continuously attached to the deck plate, as bywelding, whereas when plywood is used for the deck plate the two membersare secured to one another at close intervals by rivets, screws, orequivalent connecting members. The joists are of special shape,typically a U-shaped member in which the pair of parallel legs or railsof the U terminate in unconnected upper ends each having a flangeintegrally attached thereto and extending transversely of the rails,such flanges being provided with a multiplicity of holes for receivingthe connecting members extending downwardly from the deck plate. In suchtypicaljoist, the rails extend normally downwardly from the deck plateand the joist includes a web or base which is integral with the railsand extends between their lower ends. While the base of the U-shapedjoist is preferably continuous for the full length of the rails, theinvention encompasses within its scope equivalents such as a pair ofangle irons in which the lower ends of the downwardly extending railsare provided with a multiplicity of closely spaced connecting meanshaving the effect of rigidly joining the parallel rails together, e.g.,a series of longitudinally spaced sleeves each placed transverselybetween such rails and a stud threaded at both ends and extendingthrough both such sleeve and registering openings in the two rails, witha nut on each end of the stud to draw the pair of rails and sleevetightly together.

Such a platform may be used by itself, and may be supported on twotransverse horizontal bars of a scaffold plat form, either with theunmodified joist resting directly on the transverse bars or with groovesprovided in such joist to fit snugly over the transverse bars of theframework so that the platform will not slide between transverse bars,but must be lifted therefrom in order to make such movement possible. Ina more typical arrangement, where several platforms are to be disposedend to end to form a continuous walkway and working space, at least oneend of each joist is provided with a male member or tongue extendingbeyond the end of the platform, and such a tongue is adapted to bereceived in the female end of a joist of the adjacent platform, in theslot defined between the downwardly extending pair of rails and thecrossbar of such joist. When the joist is provided with a groove to fitover the crossmember of the scaffold framework, the tongue member isprovided with a registering groove, so disposed that when the tongue isslid into the joist of the adjacent platform.

both members may be fitted over the crossbar of the framework to bringthe ends of the deck plates of the adjoining platforms into abuttingrelationship.

The present invention will be more readily comprehended by reference tothe accompanying drawing, in which drawing:

FIG. I is a perspective view of a complete section of a preferredembodiment of the present invention, partly broken away at one corner toshow a detail of one of the joists, at the male end thereof,

FIG. 2 is an enlarged partial elevation showing two abutting sections ofthe same embodiment resting on a common transverse member of a scaffoldframework, partially broken away and sectioned to show certain details,

FIG. 3 is a cross section through one of the joists of FIG. 1, asindicated by the sectioning lines and arrows 33 thereon,

FIG. 4 is a section similar to FIG. 3 but showing an alternate joiststructure,

FIG. 5 is a perspective view, partly broken away, of a pair of sectionsof the scaffold platform of the invention disposed end to end and withadjacent ends shown resting on a common transverse member of a scaffold,

FIG. 6 is a cross section of a joist modified to provide protection forthe edge of a deck plate, and

FIG. 7 is a cross section of a pair of identical scaffold platforms ofthe invention nested for shipping or storage, showing that they occupy aminimum of space.

The scaffold platform sections ll shown in FIGS. l-3, 5 and 7 consistsof a deck plate 20 secured to a pair of underlying joists 10 by amultiplicity of closely spaced connecting members 5. Each joist extendsthe full length of the deck plate 20 and projects beyond at either endfor purposes of intermeshing with adjacent sections so that theadjoining ends of each pair of sections can use a common transversesupport furnished by the scaffold structure, although it will beapparent that, in a system where only a single section is required, thejoist need not extend beyond the ends of the deck plate. Each joist ispreferably disposed adjacent to one of the long edges of the deck plate,as illustrated, and for most of the length of the deck plate and atfemale end 11 the joist has the cross section of FIG. 3. At the oppositeor male end, the portion of the joist I0 having the cross section ofFIG. 3 terminates somewhat short of the end of deck plate 20, and hassecured thereto a bar or tongue 112 which forms the projecting end ofthejoist.

The section of the joist ll0 for most of its length comprises a pair ofrails 15 which extend generally normal to and downward from deck plate20, a pair of outwardly turned flanges 16 integrally joined to rails 15at. their upper ends, and a thickened web 18 extending between rails 15and integrally joined to both of them. The rails 15 are essentiallyparallel, and define between them a slot 19 which, at the male end ofthe joist, is set to receive the tongue 12. Tongue 12 is preferablydimensioned so that it is snugly received between rails 15, with littleor no side play, but is somewhat shorter than space 19. This permits thepreferred mounting of tongue 12 shown in particular in FIG. 2, whereinbar 12 is fixed to its joist 10 by a pair of machine screws or rivets 25which are received in registering transverse openings in bar 12 andrails 15 so that the top surface of tongue 12 is parallel to the uppersurfaces of flanges 16 but the lower surface of the rail is spaced abovethe upper surface of web 18 by a small gap or clearance 22.

In using a series of the scaffold platform sections 1, as shown in FIGS.1 and 5, both the female end 11 and the tongue end 12 of each joist arepreferably provided with transverse grooves 27, dimensioned to fltsnugly over the transverse member T of scaffold framework F, in thiscase a circular pipe member. When a female end 11 of one of the sectionsis thus mounted, and the tongue end 12 of the adjoining section ismounted on the same transverse member T, the arrangement is asillustrated in FIG. 2, with the aforementioned clearance 22 also beingformed between the tongue of the one section and the female section ofthe other. This arrangement insures that each section is supportedindependently of the other, neither requiring any support from itsadjacent brother, and makes it possible to readily remove any individualsection without disturbing the others. It also insures that accidentaldamage to one section will not be transmitted to another, as eachsection is completely independent of of the other. Also, trash whichmakes its way into a slot 19 is not likely to have the effect of raisingtongue 12 from its proper position, although it could have thisundesirable effect and the further consequence of a nonlevel transitionbetween adjacent platform sections 1 if there were no clearance 22.

In forming any one platform section 1, it is important to use a largenumber of the connecting members 5, which may be machine screws andnuts, rivets or other suitable equivalents. As an example, in asection'tested as described below 46 aluminum rivets were used in anembodiment like that shown in FIG. 1, 23 rivets per joist being used tosecure a plywood decking 20 to a pair of aluminum joists 10. The plywooddecking was 9% inch thick, and was 19 inches wide by 7 feet long. Therivets were mounted as shown, alternating between the pair of flanges 16of each joist, and the resulting spacing was on 4-inch centers along thelength of the joist. With this close spacing, the deck plate 20 andjoist 10 become almost a unitary structure, giving the combination atremendous bending strength and enabling it to support much larger loadsthan heretofore.

Connecting members may assume a wide variety of forms. Those shown inFIGS. 1-3 are the combination of filister head machine screws withmating nuts, while those shown in FIG. 4 (connecting members 5') arerivets. Any type connecting members may be used which will insure atight connection between the deck plate 20 and the flanges 16 of thejoist, a connection which is not likely to be easily loosened in servicebut can be readily removed if a wooden deck plate has become worn and isready for replacement.

The modified joist section 1' shown in FIG. 4 may utilize a deck plate20' of metal, although the combinations of deck plate and joists are notlimited to those shown in the drawings, i.e., the wooden deck plates ofFIGS. 1-3 and 5 could also use a metal deck plate and vice versa. TheFIG. 4 embodiment utilizes a joist 30 which includes a pair of angleirons 31 oriented so that the shorter leg 33 of each member 31 isdisposed beneath deck plate 20' to serve as the connecting flange whilethe longer leg 35 extends normally below the deck plate to serve as oneof the rails of the joist. The pair of rails 34 are disposed in parallelbut spaced apart relationship, and between them is disposed a series ofclosely spaced sleeves 37 which serve as spacers. Each such spacer 37receives a stud 38 which also projects through a pair of registeringopenings near the lower ends of rails 35. The projecting portions ofstud 38 are both threaded to receive a mating nut 39, and the nuts aretightened to tightly draw both rails together with sleeve 37 compressedbetween them. With such connecting members spaced sufficiently closely,e.g., about 4 inches apart in the example above mentioned, the joist 30is virtually as solid and strong in bending as the continuouslyconnectedjoist 10 of FIGS. 1-3 and 5.

EXAMPLE In the example referred to above, deck plate 20 was a unitarypiece of plywood, 15 inch thick by 19 inches wide by 6 ft. 1 1 /4 incheslong. Two aluminum joists 10 were used, disposed 7/8 of an inch from theadjacent edge extending in the longitudinal direction of the deck plate,such joists having the same 6 ft. 1 Wit-inch length as the deck plateitself. Each was disposed so that its female end 11 projected l I I/ I6inches beyond the end of the deck plate, which of course made itsopposite end terminate 1 lI/I6 inch short of the nearby end of the deckplate. Such joist had an overall depth of 2.000 inches and an overallwidth, between extremities of flanges 16, of L700 inches. Slot 19 was1.712 inches deep by 0.500 inches wide. The thickness of each rail 15and each flange 16 was 0.100 inches, while the maximum depth of web 18,at its center, was 0.288 inches.

The tongue member 12 was also made of aluminum, and had the shape of arectangular parallelapiped measuring 1% inches deep by 7/16 inch wide by6 inches in length, and it was disposed as shown in FIG. 2, so that gap22 measured 0.212 inch in depth. It was mounted in its joist 10 so that3% inches of its length extended beyond the end of the joist, of I 9/16inches extended beyond the end of deck plate 20.

As previously stated, each joist 10 was fastened to deck plate 20 by 23aluminum rivets, each such rivet being V4 inch in diameter and measuring7/8 inch in length under its preformed head prior to upsetting the freeend. Such rivets were uniformly spaced along the length of the joist,being alternately disposed in the opposed flanges 16. The resultingspacing along the length of the deck plate was 4 inches.

A single scaffold platform as thus constructed weighs only 27 pounds,and has an upper surface measuring approximately I 1 square feet. It wastested with a uniform loading along its complete length to determinewhat load was required to produce a permanent set. This did not occuruntil the uniform loading exceeded 457 pounds per foot of length, or anequivalent of a load exceeding 290 pounds per square foot of platformsurface. Such a load by far exceeds the total that may be expected inall foreseeable circumstances, including not only the weight of theworkmen and their materials but such dynamic and transitory loads as maybe expected from weather conditions and from shock loading resultingfrom other workmen walking rapidly over a particular section droppingtools and sacks of working material, etc.

Referring back to FIGS. 1, 2 and 5, it will be noted that the end ofdeck plate 20 adjacent the female ends 11 of joist 10 is provided with apair of slots 24 which overlie slots 19 of the joist in registeringrelationship therewith. While such slots 24 are not essential, they makeit possible to remove one platform 1 completely independently of theother; but for slots 24, removal of any section 1 would require raisingthe female end of the adjacent section 1 to provide the necessary fromto withdraw the end of a section 1 including the projecting tongues 12.It should also be noticed that the transverse grooves 27 in tongues 12and the female ends 11 of the joist are disposed so that the abuttingends of deck plates 20 and the small clearance therebetween are disposeddirectly over the center of the transverse bar T of the scaffoldplatform F which is received in the transverse grooves 27. Thisarrangement is believed to make for maximum safety, as there is noportion of deck plate 20 which extends to one side of transversesupporting member T from the bulk of the platform section to serve asone end of a lever, i.e., the possibility that the platform sectioncould be rotated about ember T as a pivot is eliminated.

In the modified joist ll) of FIG. 6 the prime numbers designate partssimilar to the parts of the H0. 3 joist, e.g., rails and web lb. Thereis only a single short flange 16', as the opposite flange at is extendedand bent over to fit the edge of a plywood or similar deck plate 20.Thus it includes a vertical portion 42 which butts against the edge ofthe deck plate and, preferably, a second bent over portion which engagesthe upper surface of the deck plate. The joist Ml may be dimensioned sothat its weight per lineal foot is the same as that of the joist 10 ofH6. 2. This may be accomplished, for instance, by reducing the thicknessof web 18', as illustrated.

H6. 7 illustrates how pairs of the scaffold platform 11 may be nestedfor packing and storage. With one of the pair inverted as shown, theyfit together so that the overall dimensions of the pair are onlyslightly greater than the corresponding dimensions of a single section.The pair may be tightly packed in a rectangular carton without slippinginside the carton, and many pairs like those shown in the drawing may bestacked on each other, without danger, to a considerable height.

What is claimed is:

l. A scaffold platform comprising a thin deck plate of generallyrectangular shape, a pair of joists underlying and secured to said deckplate at closely spaced intervals, said joists being generally parallelto and spaced from each other and each disposed adjacent an edge of saiddeck plate with opposed ends extending beyond the corresponding ends ofthe plate, at least a portion of each joist including one of theprojecting ends being U-shaped in cross section with a pair of outwardlybent flanges extending in opposed transverse directions from the top ofthe joist and. serving as the portion of the joist connected to saiddeck plate, said portion being adapted to receive a male end extendingfrom an adjacent platform, the opposite projecting end'of the joistbeing a male member adapted to be received in the U-shaped projectingend of another adjacent platform, said male and female ends havingregistering notches for supporting the platforms on the cross rods of ascaffolding framework.

2. A scaffold platform comprising decking elongated in one direction, atleast one stiffener joist disposed beneath said decking to extend alongits elongated direction and protruding from the ends thereof, and amultiplicity of connecting means firmly securing said joist or joists tosaid decking at closely spaced intervals along said elongated direction,one of said protruding ends of the stiffener joist being a female memberreceiving and supporting a male member of an adjacent scaffold platformand the other end being a male member receivable in a female member ofanother adjacent scaffold platform, said members being notched to bereceived and supported by cross rods of a scaffolding frameworkextending transversely of said elongated direction.

3. The scaffold platform of claim 2 in which said notches are disposeddirectly beneath the end of said deck plates.

4. The scaffold platform'of claim 41 in which said stiffener joist is aflanged U-shaped member, the flanges extending transversely of the legsin opposed directions and serving as the portions of the joist securedto the decking, and in which one of the flanges of said joist iselongated and bent to fit over and butt against an adjacent edge of thedeck plate.

1. A scaffold platform comprising a thin deck plate of generallyrectangular shape, a pair of joists underlying and secured to said deckplate at closely spaced intervals, said joists being generally parallelto and spaced from each other and each disposed adjacent an edge of saiddeck plate with opposed ends extending beyond the corresponding ends ofthe plate, at least a portion of each joist including one of theprojecting ends being U-shaped in cross section with a pair of outwardlybent flanges extending in opposed transverse directions from the top ofthe joist and serving as the portion of the joist connected to said deckplate, said portion being adapted to receive a male end extending froman adjacent platform, the opposite projecting end of the joist being amale member adapted to be received in the Ushaped projecting end ofanother adjacent platfoRm, said male and female ends having registeringnotches for supporting the platforms on the cross rods of a scaffoldingframework.
 2. A scaffold platform comprising decking elongated in onedirection, at least one stiffener joist disposed beneath said decking toextend along its elongated direction and protruding from the endsthereof, and a multiplicity of connecting means firmly securing saidjoist or joists to said decking at closely spaced intervals along saidelongated direction, one of said protruding ends of the stiffener joistbeing a female member receiving and supporting a male member of anadjacent scaffold platform and the other end being a male memberreceivable in a female member of another adjacent scaffold platform,said members being notched to be received and supported by cross rods ofa scaffolding framework extending transversely of said elongateddirection.
 3. The scaffold platform of claim 2 in which said notches aredisposed directly beneath the end of said deck plates.
 4. The scaffoldplatform of claim 4 in which said stiffener joist is a flanged U-shapedmember, the flanges extending transversely of the legs in opposeddirections and serving as the portions of the joist secured to thedecking, and in which one of the flanges of said joist is elongated andbent to fit over and butt against an adjacent edge of the deck plate.